Radon Questions & Answers

My home was built on a slab. Could I still have radon?

Yes, homes built on a slab can still have radon. Whether the home is old, new, insulated or not and regardless of construction materials it can have radon. All homes, regardless of type of construction, should be tested for radon once per year per the EPA and Health Canada.

My home is built over a crawl space. Do I need to have it tested for radon?

Yes, all homes need to be tested for radon. Radon can still enter the home through floor penetrations and the HVAC system and accumulate to elevated levels in the home.

We are moving to a new area soon and are buying a home. We recently looked at a Radon Map with zones on it and see that some areas are not in a high risk zones. Should we still test our home for radon if not in a high risk area?

Since radon levels can change from town to town and even from home to home, radon maps should not be considered the definitive source for radon level information. The EPA and Health Canada suggest all homeowners test their home for radon even if they are not in the high risk zone and that the map should not be used in lieu when there is a real estate transaction. In fact, a home can test high for radon even if the house right next door tested low.

We recently had our home tested for radon and it came back high when tested in the basement. As long as we spend little to no time in the basement, is the radon really dangerous to us?

Yes, having a high radon level in the basement can affect you in other areas of the home by the gas moving through the home via air ducts for air conditioning and the furnace, as well as natural convection.

Which homes are more likely to have higher radon levels, new homes or old homes?

All homes regardless of new or old, single or multi story, slab or with basement can have radon.

The home we bought has a radon mitigation system in it. Do I need to still test my home for radon levels?

Yes, even if a home has a radon mitigation system in it, you need to test your home for radon as the EPA and Health Canada suggests. Regular testing will ensure that the radon mitigation system is working effectively.

We have granite countertops in our kitchen and our bathrooms in our home. Will this increase the amount of radon in our home to an unsafe amount?

While the EPA and Health Canada suggest all homes should be tested for radon it also believes that currently they have insufficient data to conclude that the types of granite commonly used in countertops will significantly increase the indoor radon levels. Both EPA and Health Canada believe that the radon from granite will be insignificant.

Does it matter what time of year I test my home for radon?

No, testing can be done at any time of the year. Testing does require the home to have all of its windows and doors kept closed during the test, but central heating and air conditioning can operate. If the windows and doors cannot be kept closed during the test, it would be best to wait until the conditions allow for it.

I’ve heard radon testing is expensive. Are the risks significant enough to justify the test?

Radon testing is done by a professional and at a relatively minor cost. Tests cost less than a few hundred dollars, and knowing the results should bring you significant peace of mind.

Our radon level came in very close to 4.0 pCi/L (the US standard) or 200 bequerels (Canadian standard) and we see that’s well above the World Health Organization standard of 2.7 pCi/L (100 bequerels). Should we take steps to lower the level even though it’s below 4.0 pCi/L?

Less radon in your home is always better. Both the EPA and Health Canada recommend taking action above those levels, but for your own peace of mind, you should consider mitigation systems at any significant level of radon. Consult with your radon professional for more advice.How can radon affect my health?

The only known health risk associated with exposure to high levels of radon in indoor air is an increased lifetime risk of developing lung cancer. The risk from radon exposure is long term and depends on the level of radon, how long a person is exposed and their smoking habits. If you are a smoker and are exposed to elevated levels of radon your risk of developing lung cancer increases significantly.

How much will it cost to mitigate my house?

The cost of reducing radon in your house depends on how your home was built and the extent of the radon problem. The average radon remediation process, typically done using a contractor, will cost between $1,500 – $3,000. The cost is much less if a passive system was installed during construction.

I am a smoker. Does radon affect me more than a non-smoker?

Yes. The risk from radon exposure for a smoker (including those exposed to second hand smoke) is much greater than for a non-smoker. For example, if you are a lifelong smoker but are not exposed to radon, your risk of getting lung cancer is one in ten. If you add exposure to a high level of radon, your risk becomes one in three. On the other hand, if you are a non-smoker, your lifetime lung cancer risk at the same high radon level is only one in twenty.

Are children more at risk from radon than adults?

Children have been reported to be at greater risk than adults for certain types of radiation exposure, but there is currently no conclusive data on whether children are at greater risk than adults from radon.

What about drinking water that contains radon?

Research has shown that drinking water that contains radon is far less harmful than breathing radon. When the ground produces radon, it can dissolve and accumulate in water from underground sources, such as wells. When water that contains radon is agitated when used for daily household requirements, radon gas escapes from the water and goes into the air. The health risk is not from ingestion but from radon inhalation.

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